Ferns are perennial plants commonly grown for their attractive foliage and ease of care. The plants grow from rhizomes that creep along the surface of the soil, and many gardeners consider them to be ornamental. Ferns can grow from 6 inches to 5 feet in height, depending on the variety, though most reach a fairly compact size when grown indoors. Native to tropical and sub-tropical regions, ferns require constant warm temperatures and a humid environment to thrive as indoor plants.
Keep ferns in a location that receives two to four hours of sunlight each day, such as a north-facing window. Use a growing medium made of one part peat moss and one part potting soil to provide adequate drainage and fertility for indoor ferns.
Maintain a temperature of 60 to 70 degrees Fahrenheit during the day and 50 to 60 degrees Fahrenheit at night for best results. Most ferns will not thrive if temperatures are less than 50 degrees Fahrenheit, but check the individual species to find out the minimum tolerated temperature.
Fill a shallow tray with pebbles, and then add water until the pebbles are almost completely covered. Keep the fern's container on top of the pebbles at all times to increase the relative humidity near the plant. Replenish the water whenever necessary.
Water ferns once every week, allowing the soil to dry slightly between applications. Reduce watering frequency during winter to once every 10 days. Apply water during the early morning so excess moisture can evaporate before evening.
Feed indoor fern plants once a month from April through September using a liquid houseplant fertilizer. Apply at half the rate recommended by the manufacturer to prevent scorching the leaves. Do not fertilize during winter, while ferns are growing less actively.